.\"
.\" libdivecomputer
.\"
.\" Copyright (C) 2017 Kristaps Dzonsons <kristaps@bsd.lv>
.\"
.\" This library is free software; you can redistribute it and/or
.\" modify it under the terms of the GNU Lesser General Public
.\" License as published by the Free Software Foundation; either
.\" version 2.1 of the License, or (at your option) any later version.
.\"
.\" This library is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
.\" Lesser General Public License for more details.
.\"
.\" You should have received a copy of the GNU Lesser General Public
.\" License along with this library; if not, write to the Free Software
.\" Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
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.\"
.Dd January 5, 2017
.Dt DC_PARSER_GET_FIELD 3
.Os
.Sh NAME
.Nm dc_parser_get_field
.Nd extract a field from a parsed dive
.Sh LIBRARY
.Lb libdivecomputer
.Sh SYNOPSIS
.In libdivecomputer/parser.h
.Ft dc_status_t
.Fo dc_parser_get_field
.Fa "dc_parser_t *parser"
.Fa "dc_field_type_t type"
.Fa "unsigned int flags"
.Fa "void *value"
.Fc
.Sh DESCRIPTION
Extract a field from a dive,
.Fa parser ,
previously initialised with
.Xr dc_parser_set_data 3 .
The
.Fa value
field type depends upon the
.Fa type .
The
.Fa flags
field is ignored for all types but
.Dv DC_FIELD_GASMIX
and
.Dv DC_FIELD_TANK .
.Pp
The
.Fa type
may be one of the following values:
.Bl -tag -width Ds
.It Dv DC_FIELD_DIVETIME
Time (duration) of dive in seconds.
The
.Fa value
must be an
.Vt unsigned int .
.It Dv DC_FIELD_MAXDEPTH
Maximum depth in metres.
The
.Fa value
must be a
.Vt double .
.It Dv DC_FIELD_AVGDEPTH
Average depth (over all samples) in metres.
The
.Fa value
must be a
.Vt double .
.It Dv DC_FIELD_GASMIX_COUNT
Number of different gas mixes used in this dive.
The
.Fa value
must be a
.Vt unsigned int .
.It Dv DC_FIELD_GASMIX
Mixture for a particular gas.
The
.Fa value
must be a
.Vt dc_gasmix_t ,
which has
.Vt double
fields for
.Va oxygen ,
.Va helium ,
and
.Va nitrogen .
These are set to the unit fraction of gas (not percentage).
The
.Fa flags
value is interpreted as the gas mixture index, which must be less than the
value of
.Dv DC_FIELD_GASMIX_COUNT .
.It Dv DC_FIELD_SALINITY
The water salinity as a
.Vt dc_salinity_t
field, which consists of a
.Va type ,
.Dv DC_WATER_FRESH
or
.Dv DC_WATER_SALT ,
and the salinity
.Va density .
.It Dv DC_FIELD_ATMOSPHERIC
Atmospheric pressure in bar.
The
.Fa value
field must be a
.Vt double .
.It Dv DC_FIELD_TEMPERATURE_SURFACE
Air temperature (at the surface) in Celsius.
The
.Fa value
field must be a
.Vt double .
.It Dv DC_FIELD_TEMPERATURE_MINIMUM
Minimum water temperature surface in Celsius.
The
.Fa value
field must be a
.Vt double .
.It Dv DC_FIELD_TEMPERATURE_MAXIMUM
Maximum water temperature in Celsius.
The
.Fa value
field must be a
.Vt double .
.It Dv DC_FIELD_TANK_COUNT
The number of tanks as an
.Vt unsigned int .
.It Dv DC_FIELD_TANK
Tank configuration as a
.Vt dc_tank_t .
This structure consists of a
.Va gasmix ,
which may be retrieved with
.Dv DC_FIELD_GASMIX ;
.Va type ,
the tank volume units as
.Dv DC_TANKVOLUME_NONE ,
.Dv DC_TANKVOLUME_IMPERIAL ,
or
.Dv DC_TANKVOLUME_METRIC ;
.Va volume ,
the tank volume in bar or zero if the tank is
.Dv DC_TANKVOLUME_NONE ;
.Va workpressure ,
the work pressure in bar or zero if
.Dv DC_TANKVOLUME_NONE
and maybe zero if
.Dv DC_TANKVOLUME_METRIC ;
.Va beginpressure
and
.Va endpressure
being the pressures at start and finish in bar.
The
.Fa flags
value is the tank index.
.It Dv DC_FIELD_DIVEMODE
Mode of the dive:
.Dv DC_DIVEMODE_FREEDIVE
for free-diving,
.Dv DC_DIVEMODE_GAUGE
for gauge (i.e., running as a record and not computing, say,
decompression events),
.Dv DC_DIVEMODE_OC
for standard open-circuit diving, and
.Dv DC_DIVEMODE_CCR
and
.Dv DC_DIVEMODE_SCR
for respectively closed circuit and semi closed circuit
.Dq rebreather
diving.
.El
.Sh RETURN VALUES
Returns
.Dv DC_STATUS_SUCCESS
if the field was retrieved,
.Dv DC_STATUS_UNSUPPORTED
if the field is not supported by the device, or other error messages on
further failure.
.Sh SEE ALSO
.Xr dc_parser_set_data 3
.Sh AUTHORS
The
.Lb libdivecomputer
library was written by
.An Jef Driesen ,
.Mt jef@libdivecomputer.org .
The manpages were written by
.An Kristaps Dzonsons ,
.Mt kristaps@bsd.lv .
